<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      * {
        margin: 0;
        padding: 0;
      }
      a {
        text-decoration: none;
      }
      .banner {
        width: 520px;
        height: 190px;
        margin: auto;
        margin-top: 100px;
        position: relative;
      }
      .banner > img {
        display: block;
        width: 520px;
        height: 190px;
      }
      .ab-arrow {
        position: absolute;
        background-color: rgba(0, 0, 0, 0.3);
        color: white;
        width: 20px;
        height: 20px;
        line-height: 20px;
        text-align: center;
      }
      .ab-arrow-left {
        top: 50%;
      }
      .ab-arrow-right {
        top: 50%;
        right: 0;
      }
      .banner ul {
        position: absolute;
        width: 110px;
        height: 20px;
        padding: 4px;
        background-color: rgba(0, 0, 0, 0.3);
        bottom: 0;
        left: 50%;
        margin-left: -50px;
        border-radius: 10px;
      }
      .banner ul li {
        list-style: none;
        float: left;
        width: 18px;
        height: 18px;
        border-radius: 9px;
        margin: 0px 2px;
        background-color: white;
      }
      .banner .sel {
        background-color: yellow;
      }
    </style>
  </head>
  <body>
    <div class="banner">
      <a class="ab-arrow ab-arrow-left" href="#">></a>
      <a class="ab-arrow ab-arrow-right" href="#">&lt;</a>
      <img src="./img/tb1.jpg" alt="" />
      <ul>
        <li class="sel"></li>
        <li></li>
        <li></li>
        <li></li>
        <li></li>
      </ul>
    </div>
  </body>
</html>
